Abstract

Electron spin resonance studies have been carried out on Cu2+doped K2Co(SO4)2 · 6H2O at different temperatures. The resolution of the spectrum is found to be maximum at about 210 °K and the electric field symmetry around Cu2+ at this temperature is found to be rhombic having the spin‐Hamiltonian constants, gz = 2.330 ± 0.005, gx = 2.227 ± 0.005, gy = 2.053 ± 0.005, Az ≃ (60 ± 2) × 10−4 cm−1, Ax ≃ (52 ± 2) × 10−4 cm−1, and Ay ≃ (59 ± 2) × 10−4 cm−1. These spin‐Hamiltonian parameters are found to be temperature dependent. The linewidth of the copper hyperfine lines are found to increase with decreasing temperature which is most probably brought about by the superposition of a very broad Co2+ line on Cu2+ hyperfine line.